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Topic: PIA B737 Landing Gear Failure In Muscat / Oman
Username: chieft
Posted 2013-02-11 05:16:27 and read 19502 times.

A Pakistan International Airlines B737 passenger plane crash-landed on the runway of Oman's main airport in Muscat today:

http://www.emirates247.com/pia-crash...airport-closed-2013-02-11-1.494619

[Edited 2013-02-11 05:16:58]

http://avherald.com/h?article=45d93bd3


[Edited 2013-02-11 05:18:13]

[Edited 2013-02-11 05:19:11]

Topic: PIA B737 Landing Gear Failure In Muscat / Oman
Username: TK787
Posted 2013-02-11 05:24:07 and read 19375 times.

Sounds like it happened after landing and then the front landing gear collapsed.

Topic: PIA B737 Landing Gear Failure In Muscat / Oman
Username: teneriffe77
Posted 2013-02-11 05:35:00 and read 19220 times.

If you look at he picture from avherald you can see it's not the nose gear but the left main landing gear and the plane is now resting it's left engine. As far as damage goes you've got the left engine, left main gear and possible left wing due to the stress of dragging the engine along the runway.

Topic: PIA B737 Landing Gear Failure In Muscat / Oman
Username: comorin
Posted 2013-02-11 05:36:02 and read 19221 times.

Please, what are the main reasons for a landing gear collapse?

Thanks in advance.

Topic: PIA B737 Landing Gear Failure In Muscat / Oman
Username: TK787
Posted 2013-02-11 05:36:55 and read 19189 times.

Quoting teneriffe77 (Reply 2):
If you look at he picture from avherald

My bad, I didn't see that second link.

Topic: PIA B737 Landing Gear Failure In Muscat / Oman
Username: TK1244
Posted 2013-02-11 05:52:13 and read 18995 times.

Good to hear no one was injured

Topic: PIA B737 Landing Gear Failure In Muscat / Oman
Username: na
Posted 2013-02-11 05:59:42 and read 18917 times.

Crash-landing sounds a "bit" exaggerated. PIA might be disappointed to see that this hit the only 733 in the fleet which isnt so old its not worth repairing. All other 733s they have are very old, only this one is from 1992.
Still, it could be a write-off as PIA is retiring the 733 in the coming months and dozens of age-mates have been scrapped or retired recently, among them many LH birds, and the whole fleets of Batavia, Webjet, Aerosvit etc.

[Edited 2013-02-11 06:07:15]

Topic: PIA B737 Landing Gear Failure In Muscat / Oman
Username: migair54
Posted 2013-02-11 06:42:46 and read 18436 times.

I can´t see the slides, how did they leave the plane?? interesting if after that crash landing they didn´t evacuate the plane... engine has fuel, hyd, electrics... plus sparks and heat from the friction with the runway, really dangerous situation.

according to the metar and runway 26L they landed with tail wind from the left, so this could be another factor, a hard landing with the left main gear can create this kind of damage, specially variable and gusty wind, excessive banking to correct a change or a gust, and impact the runway not fully align.... that´s hard for the L/G.

to know if it will be a write off we have to wait but usually the problem with this accidents are the structural damage in the wing, but with a 21 years old plane i see it difficult to spend too much money to fix.

Topic: PIA B737 Landing Gear Failure In Muscat / Oman
Username: UK_Dispatcher
Posted 2013-02-11 06:53:06 and read 18294 times.

My most recent flight was on this aircraft, on 29th January from KHI to AUH.

Knowing that most of the PIA B733s were early build ones, I was surprised to see this one was a 1992-build ex-Government aircraft when I checked afterwards. I said to my friend/fellow aircraft nutter when we flew it that despite this aircraft not being the main 'aviation attraction' of our trip, I was actually glad to get on a PIA B733 since they wouldn't be around for much longer. Little did I know this aircraft had less than 2 weeks to go!

Ian

Topic: PIA B737 Landing Gear Failure In Muscat / Oman
Username: Revelation
Posted 2013-02-11 07:03:52 and read 18158 times.

Ahh, another 737 classic bites the dust...

Not sure how bad a "crash" it is.

Glad there were no injuries.

Topic: PIA B737 Landing Gear Failure In Muscat / Oman
Username: Pihero
Posted 2013-02-11 07:10:09 and read 18043 times.

Please stop the sensationalism
1/- The wind was variable, from 030° to 160°, probably caused by a small frontal passage.
2/- Pilots don' t have anything to do with the ATC choice of runway in use. Apparently everybody was satisfied with the choice of runway.Otherwise, they would have requested 08R.
3/- The most glaring aspect of the incident is that the collapse of the left main gear happened after landing, quite some time after touchdown, as the deployed reverser shows in the picture
4/- Landing gears are buit to take a lot of abuse - for instance, no de-crabbing on strong cross winds on landing, so I do not think the failure came frrom a botched landing... my money is more on a gear-down latching problem
5/- "excessive banking", as you said would have caused the left engine to scrape the runway... there doesn't seem to be any traces on the pavement.

Topic: PIA B737 Landing Gear Failure In Muscat / Oman
Username: RussianJet
Posted 2013-02-11 07:11:50 and read 18042 times.

Quoting clydenairways (Reply 7):
It's hardly a crash.

Maybe, but it's hardly a typical landing either. It's a life-threatening thing to have the gear collapse on landing.

Quoting Revelation (Reply 10):
Ahh, another 737 classic bites the dust...

Yeah, a real shame to see.

Topic: PIA B737 Landing Gear Failure In Muscat / Oman
Username: rfields5421
Posted 2013-02-11 08:37:37 and read 17488 times.

Quoting Pihero (Reply 11):
4/- Landing gears are buit to take a lot of abuse - for instance, no de-crabbing on strong cross winds on landing, so I do not think the failure came frrom a botched landing... my money is more on a gear-down latching problem

I've seen a lot of photos over the decades of landing gear collapses, however, only a few of those look like this one where the gear folded inward toward the stowed position.

Some issue with the latching seems quite likely.

Topic: PIA B737 Landing Gear Failure In Muscat / Oman
Username: FltMech747
Posted 2013-02-11 12:56:53 and read 11345 times.

Looks like a Damper Assy failure which causes the wheels to twist "shimmy" followed by the down lock failing.

Just saying... 

Topic: PIA B737 Landing Gear Failure In Muscat / Oman
Username: Pihero
Posted 2013-02-11 14:12:13 and read 9702 times.

Looking back at the photo, there's something hanging from under the wing, apparently from the wheel well. Some people think that's the diagonal brace... no wonder the gear collapsed, then.
Another remarked that the tyres didn't show any sign of a blow up or destruction, which confirmed that the collapse happened near the very end of the roll-out.
What do you think, rfields5421 and FltMech747 ?

Topic: PIA B737 Landing Gear Failure In Muscat / Oman
Username: zbbylw
Posted 2013-02-11 14:56:19 and read 8832 times.

Quoting Pihero (Reply 11):
2/- Pilots don' t have anything to do with the ATC choice of runway in use.

You're joking right? If I don't like the runway of choice I will be requesting otherwise. If one runway has a strong tailwind would you just happily shoot the approach and land? How about a strong crosswind with an icy runway? If for what ever reason you do not feel that it's safe to land on a particular runway you don't.

Topic: PIA B737 Landing Gear Failure In Muscat / Oman
Username: Pihero
Posted 2013-02-11 15:56:14 and read 7787 times.

Quoting zbbylw (Reply 17):
If I don't like the runway of choice I will be requesting otherwise.

...and that's EXACTLY what I wrote, one sentence further :

Quoting Pihero (Reply 11):
Apparently everybody was satisfied with the choice of runway.Otherwise, they would have requested 08R.

Stress is mine on this post.

Topic: PIA B737 Landing Gear Failure In Muscat / Oman
Username: rfields5421
Posted 2013-02-11 16:07:43 and read 7597 times.

Quoting migair54 (Reply 8):
I can´t see the slides, how did they leave the plane?? interesting if after that crash landing they didn´t evacuate the plane...

This collapse wasn't a crash. There was not indication of fire or additional danger.

Using the slides to get people off the aircraft is a GUARANTEE OF INJURIES - easily possible for serious injuries to occur. Even more so in today's world when people insist upon carrying dangerous objects onto the slides.

Slide evacuation is a precaution when it is critical to get people off the plane immediately due to imminent danger.

I see nothing in the pictures to indicate an imminent danger.

As to how the folks get off the plane - a stair brought to the rear doors.

Quoting Pihero (Reply 16):
Some people think that's the diagonal brace... no wonder the gear collapsed, then.
Another remarked that the tyres didn't show any sign of a blow up or destruction, which confirmed that the collapse happened near the very end of the roll-out.
What do you think, rfields5421 and FltMech747 ?

It is obvious that this was a relative low speed failure of the gear. Not to pre-judge - but this really looks like a mechanical failure. I'd hate to be the last mechanic to work on that gear.

Topic: RE: PIA B737 Landing Gear Failure In Muscat / Oman
Username: Roseflyer
Posted 2013-02-11 19:48:57 and read 6130 times.

Landing gear components wear over time. On the 737 the landing gear must be overhauled every 10 years where all the moving parts are taken off the airplane for restoration. It is normal for cracks to develop. The looks like a down lock, retract actuator, drag brace, etc could have broken. These components do not support the weight directly but rather support any side loads. That can explain why the fear deployed and didn't buckle immediately upon landing.

I personally would be curious when the gear was last overhauled. Since th plane is 21 years old it may have just been overhauled or it could be due for one soon and is not make it.

Topic: RE: PIA B737 Landing Gear Failure In Muscat / Oman
Username: debonair
Posted 2013-02-12 00:29:25 and read 4703 times.

Quoting na (Reply 6):
All other 733s they have are very old, only this one is from 1992.
Still, it could be a write-off as PIA is retiring the 733 in the coming months and dozens of age-mates have been scrapped or retired recently

I had a deja vu - same kind of accident happened back in 2011: http://avherald.com/h?article=444461f4&opt=0

This was a write-off, so I assume the same for PIA.

Topic: RE: PIA B737 Landing Gear Failure In Muscat / Oman
Username: Speedbird128
Posted 2013-02-12 06:49:05 and read 2828 times.

Pretty far off the side of the runway too...


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